CHEMOSPHERE
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2017
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IF 4.208
Xiaoyuan Man,Xun-an Ning,Haiyuan Zou,Jieying Liang,Jian Sun,Xingwen Lu,Jiekui Sun
This paper proposes a combined ultrasound (US) and zero-valent iron/EDTA/Air (ZEA) system to remove polycyclic aromatic hydrocarbons (PAHs) from textile dyeing sludge . The removal efficiencies of 16 PAHs using ZEA, US/Air (air injected into the US process), and US/ZEA treatments were investigated, together with the effects of various operating parameters. The enhanced mechanisms of US and the role of reactive oxygen species (ROS) in removing PAHs in the US/ZEA system were explored. Results showed that only 42.5% and 32.9% of ∑16 PAHs were removed by ZEA and US/Air treatments respectively, whereas 70.1% were removed by US/ZEA treatment, (with favorable operating conditions of 2.0 mM EDTA, 15 g/L ZVI, and 1.08 w/cm 3 ultrasonic density). The US/ZEA system could be used with a wide pH range. US led to synergistic improvement of PAHs removal in the ZEA system by enhancing sludge disintegration to release PAHs and promoting ZVI corrosion and oxygen activation. In the US/ZEA system, PAHs could be degraded by ROS (namely OH, O 2 − /HO 2 , and Fe(IV)) and adsorbed by ZVI, during which the ROS made the predominant contribution. This study provides important insights into the application of a US/ZEA system to remove PAHs from sludge.
研究领域:
环境科学
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污染控制
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化学工程
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DOI
PubMed
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2023
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IF 22.1
Minzi Liao,Shengxi Zhao,Kai Wei,Hongwei Sun,Lizhi Zhang
Cr(III)-organic complexes removal from wastewater is challenging to decompose the complexes without producing toxic Cr(VI). Herein we demonstrated that oxalated zero-valent iron (Ox-ZVI) could one-step decomplex 95.4% of Cr(III)-EDTA with 94.2% removal of total Cr and 60.5% removal of TOC without generating Cr(VI) at pH 6.0. Ox-ZVI with FeC 2 O 4 shell preferred to adsorb and activate O 2 to produce more reactive species than ZVI with iron oxide shell, while the generated 1 O 2 could selectively break the Cr-O and Cr-N bond to precisely decomplex Cr(III)-EDTA without producing Cr(VI). The released Cr(III) was in-situ precipitated on the surface of ZVI in Cr(OH) 3 form. Interestingly, •OH preferred the effective degradation of the released EDTA ligand to the oxidation of the chelated Cr(III) at pH 6.0. This study offers a green and facile method for the Cr(III)-organic complexes treatment, and also sheds light on the importance of reactive species adjustment for the precise pollutant control.
研究领域:
环境科学
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化学工程
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DOI
高影响因子
ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY
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2018
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IF 3.974
Di Guo,Amjad Ali,Chunyan Ren,Juan Du,Ronghua Li,Altaf Hussain Lahori,Ran Xiao,Ziyang Zhang,Zengqiang Zhang
Phytoremediation of contaminated soil is an in-situ reclamation technique for removal of potentially toxic metals through hyperaccumulator plants. Potherb mustard ( Brassica juncea, Coss. ) is less explored for its assisted phytoextraction potential to restore and accelerate potentially toxic metals removal from smelter-contaminated soil. In this study, different levels of ethylene diamine tetraacetic acid (EDTA) alone and combined with citric acid (CA) and oxalic acid (OA) were applied in a greenhouse pot experiment. Chelates added on 25th d and 25/35th d after sowing, enhanced cadmium (Cd) and zinc (Zn) bioavailability in soil due to complexation. As a result, Cd and Zn in shoot and root were significantly amplified by 1.7, 2.15 and 1.93, 2.7 folds than control, respectively. Shoot and root dry weight significantly reduced and ranged between 4.13–9.91 and 0.21–0.77 g pot −1 , respectively. The toxicity induced by potentially toxic metals in plant imposed a series of biological responses. Plant antioxidants like Phenylalanine ammomialyase (PAL), polyphenol oxidase (PPO) Catalase (CAT) content increased, except the peroxidase (POD) with the addition of chelating agents . Besides, biological concentration factor (BCF) of Cd and Zn, translocation factor (TF) of Cd were notably elevated (>1.0), while TF of Zn was reduced. Pearson correlation analysis showed a positive relation between DTPA-extractable and shoot concentration of Cd and Zn, whereas it showed negative correlation with plant dry weight. In general, chelate-assisted phytoremediation of smelter contaminated soil proved effective in this study, and followed the order: EDTA > EDTA + CA ≈ EDTA + OA > CK.
研究领域:
环境科学
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植物学
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DOI
PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2020
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IF 9.038
Mengke Li,Liang Hu,Hui Zhong,Zhiguo He,Wei Sun,Daolin Xiong
The recycling of solid wastes is obligable as it can reduce the environmental pollution and prevent the diffusion of secondary pollution. In this study, a novel cheap adsorbent was prepared by modifying electrolytic manganese residue (EMR) with EDTA. The maximum adsorption capacity of adsorbents for diethyl dithiocarbamate (DDTC) was 133.46 mg/g under initial pH of 7.32 at room temperature. Adsorption kinetics study revealed the DDTC adsorption on EDTA-EMR is mainly controlled by chemisorption and isotherm studies implied the adsorption is a monolayer process. Mechanism exploration found that the DDTC molecules could enter into the holes of EDTA-EMR, and the transition metal-based sorption sites were crucial for the target molecule immobilization and chelation. High pH value (> 10) was found to have inhibited the adsorption capacity of adsorbent, which should be due to the fact that the decreasing of functional groups on adsorbents surface and the competition between DDTC and OH – . The ionic strength has negligible effect on the adsorption and the as-synthesized adsorbents showed excellent performance after five cycles. The overall results reveal that EDTA-EMR is a promising adsorbent ascribed by its low cost, good recyclability and excellent adsorption capacity.
研究领域:
环境科学
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化学工程
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DOI
PubMed
高影响因子
ENVIRONMENTAL TECHNOLOGY
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2023
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IF 2.8
Wenyan Wang,Yunlan Xu,Dengjie Zhong
Ni-EDTA is widely present in electroplating effluents. It cannot be effectively removed by traditional wastewater treatment methods due to its chemical stability. In this study, copper sulphide/cuprous sulphide doped zero-valent iron@carbon (ZVI@C/CuS/Cu2S) was prepared to active peroxymonsulphate (PMS) to decomposition Ni-EDTA. The ZVI@C/CuS/Cu2S + PMS process shows excellent performance under neutral or even alkaline conditions. This is due to the acceleration of ZVI electron transport by CuS/Cu2S, the autocatalysis of CuS/Cu2S itself, and the synergistic effect of CuS/Cu2S and Ni-EDTA. The removal efficiency of 50 ppm Ni-EDTA electroplating effluents reached 99.53% at 10 min, and the discharge water can meet the Chinese emission standard. The influences of the main parameters such as initial pH value, catalyst, PMS and initial Ni-EDTA concentration on removal efficiency was systematically investigated.
研究领域:
环境科学
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材料科学
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产品关联
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2024
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IF 8.1
Shuyu Qi,Zilong Zhao,Yingqing Ou,Lu Liu,Yatao Ren,Wenyi Dong,Hongjie Wang,Zigong Ning
In this study, a calcium-rich biochar (CRB)-enhanced dual reaction center (DRC) Fenton-like catalyst, Cu-Al 2 O 3 -CRB, was synthesized for the decomplexation of a typical heavy metal complex pollutant, Ni-ethylenediaminetetraacetic acid (Ni-EDTA), in industrial wastewater. After a 90-minute reaction, the removal rate of Ni(II) could reach 95.2%, regardless of the initial solution pH. Various characterization analyses confirmed the formation of electron-rich Cu regions and electron-deficient Al and C regions in the Cu-Al 2 O 3 -CRB catalyst. The catalytic oxidation experiments, chronoamperometry tests, and reactive oxygen species (ROSs) detection further revealed the roles of biochar and CaCO 3 on the catalytic behavior of Cu-Al 2 O 3 -CRB catalyst. The presence of biochar not only enhanced the loading of Cu species but also introduced additional electron transfer channels, while CaCO 3 further interacted with biochar/Cu species to amplify the electron cloud density surrounding Cu. The improvement of electronic polarization facilitated the activation of H 2 O 2 and the generation of •O 2 – , 1 O 2 and •OH. Contrary to conventional interfacial reactions, the weak adsorption between Cu-Al 2 O 3 -CRB and Ni-EDTA due to the electrostatic repulsion, led to the decomplexation reactions primarily occurring in the solution phase, rather than on the catalyst surface. This study sheds light on the potential of Cu-Al 2 O 3 -CRB as a DRC catalyst and emphasizes the significance of contaminant properties when using this kind of catalysts.
研究领域:
环境科学
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催化化学
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DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2023
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IF 8.6
Meiling Chen,Lei Zhou,Xiuqin Xiong,Shijun Zhu,Xinkai Yuan,Boyin Yan,Bingrui Ma,Jiachuang Shao,Liming Yang,Xubiao Luo,Penghui Shao
Conventional advanced oxidation processes were used to treat heavy metal complexes. However, a considerable amount of oxidants was required to enable effective oxidative degradation, which led to a significant increase of the treatment costs and subsequent difficulties in the sludge disposal. Based on the abundance of anions in heavy metal wastewater, the effects of anions on the in-situ degradation of Ni-EDTA in an oxidant-free electrochemical system with boron-doped diamond (BDD) as the anode were investigated. The presence of Cl - was found to exert a significant effect on improving the degradation process. Moreover, pH had little effect on the removal of nickel (Ni) and Ni-EDTA within a specific pH range (1 < pH < 9). The removal efficiencies of Ni and TOC reached 100 % and 77.45 %, respectively, at pH 2.16 with 0.4 M NaCl electrolyte, 2 mM Ni-EDTA concentration, and a current density of 50 mA/cm 2 . •OH and Cl• played crucial roles in the removal of Ni-EDTA by disrupting the chelation sites of Ni and EDTA molecules. The released Ni 2+ ions could active the H 2 O 2 in-situ generated at the cathode to produce •OH. The formation of the precipitation products such as NiOOH, Ni(OH) 2 , and NiCO 3 in the Cl - /BDD system were conform based on the XRD and XPS analyses, which suggested the possible pathways for the removal of Ni 2+ and Ni 3+ . Finally, the possible degradation pathways of Ni-EDTA were proposed based on the identification of intermediate products using UPLC-MS.
研究领域:
环境科学
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电化学工程
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产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2023
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IF 8.6
Yongli Shi,Jie Feng,Zhaoxin Zhang,Ningning Cao,Jiahao Li,Heping Li,Linji Li,Quanxian Hua,Qun Ma,Kai Zhang
Polypyrrole-based adsorbents have emerged in removing Cr(VI) from wastewater based on their reduction, chelation, electrostatic attraction and ion exchange. However, it is still a formidable challenge to remove metal cations simultaneously due to electrostatic repulsion. In fact, metal ions originating from industrial activities such as chemical manufacturing and metal electroplating are always complex and multifarious. Here, we report a EDTA-crosslinking-chitosan/polypyrrole composite (EDTA-CS/PPy) with multiple types of adsorption sites (carboxyl, hydroxyl, amino), successfully realizing simultaneous removal of Cr(VI) anions and other metal cations. The maximum adsorption capacities of Cr(VI), Cu(II), Pb(II) and Cd(II) reach up to 401.25, 59.03, 77.81 and 68.31 mg/g, respectively. The adsorption mechanism is attributed to coupling interactions of the reduction, chelation, electrostatic attraction and ion exchange between targeted metal ions and EDTA-CS/PPy, investigated by experiments and DFT theories. Notably, the adsorption capacity of EDTA-CS/PPy keeps stability after three adsorption–desorption cycles. These findings may promote potential applications of EDTA-CS/PPy adsorbents in highly efficient treatment of coexisting toxic metal ions from wastewater.
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
CHEMOSPHERE
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2023
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IF 8.8
Jiaming Zhang,Chao Yu,Longqian Xu,Zhenyu Zhao,Deli Wu
Electro-enhanced metal-free boron/peroxymonosulfate (B/PMS) system has demonstrated potential for efficient metal-organic complexes degradation in an eco-friendly way. However, the efficiency and durability of the boron activator are limited by associated passivation effect. Additionally, the lack of suitable methods utilizing in-situ recovery of metal ions liberated from decomplexation causes huge resource waste. In this study, B/PMS coupled with a customized flow electrolysis membrane (FEM) system is proposed to address above challenges with Ni-EDTA used as the model contaminant. Electrolysis is confirmed to remarkably promote the activation performance of boron towards PMS to efficiently generate • OH which dominated Ni-EDTA decomplexation in the anode chamber. It is revealed that the acidification near the anode electrode improves the stability of boron by inhibiting passivation layer growth. Under optimal parameters (10 mM PMS, 0.5 g/L boron, initial pH = 2.3, current density = 68.87 A/m 2 ), 91.8% of Ni-EDTA could be degraded in 40 min, with a k obs of 6.25 × 10 −2 min −1 . As the decomplexation proceeds, nickel ions are recovered in the cathode chamber with little interference from the concentration of co-existing cations. These findings provide a promising and sustainable strategy for simultaneous metal-organic complexes removal and metal resources recovery.
研究领域:
环境科学
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化学工程
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产品关联
DOI
PubMed
高影响因子
APPLIED SURFACE SCIENCE
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2025
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IF 6.9
Huiwei Ding,Zhihao Wang,Yu Guan,Rongyao Ma,Xin Tang,Qiaofeng Han
The effect of EDTA-2Na on the photocatalytic performance of bismuth-based compounds varied with their chemical compositions and EDTA dosage. For Bi 2 O 3 and Bi 5 O 7 I with high Bi/anions ratios, coordinating with EDTA-2Na at molar ratios of 1.5:1 for Bi 2 O 3 and 5:1 for Bi 5 O 7 I significantly improved photocatalytic activity of methyl violet (MV, 50 mg·L -1 ) degradation under visible irradiation, with apparent rate constants ( k ) of 0.0715 min −1 and 0.0261 min −1 , which were 102 and 44 times of those for pure Bi 2 O 3 and Bi 5 O 7 I, respectively. Besides, these samples also exhibited enhanced adsorption performance to cation dye MV due to decreased zero zeta potential. However, If the molar ratio of EDTA to Bi 2 O 3 exceeded 4:1 and the molar ratio of EDTA to Bi 5 O 7 I exceeded 5:1, the samples possessed the poor photocatalytic performance for the degradation of MV, even inferior to pure Bi 2 O 3 and Bi 5 O 7 I. Conversely, BiOX (X = Br, I) and Bi 2 O 2 CO 3 with low Bi/anion ratios didn’t show significant improvement in photocatalytic activity, and BiVO 4 and Bi 2 MoO 6 with lower Bi/anion ratios exhibited even worse photocatalytic performance after coordinating with EDTA-2Na. Photocatalytic mechanism suggests that EDTA-2Na’s electron transfer capabilities to the conduction band of high Bi/anion ratio compounds promote reactive oxygen species generation, enhancing their photocatalytic performance. For the low Bi/anion ratio compounds, the electrons of EDTA would transit to VB and trap the holes, hindering the hole-dominant photo catalysis process.
研究领域:
材料科学
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环境科学
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产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2021
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IF 19.503
Sheng Liang,Xiaoting Hu,Haolin Xu,Zhenchao Lei,Chaohai Wei,Chunhua Feng
The present study aims to gain molecular insights into how peroxomonosulfate (PMS) reacts with ethylenediaminetetraacetic acid (EDTA)-Ni II at alkaline pH by conducting experimental tests and density functional theory (DFT) calculations. We first show experimental evidence that the decomplexation of EDTA-Ni II and simultaneous formation of Ni hydroxide precipitates can be successfully achieved with the addition of PMS under alkaline conditions. At pH 11.0 or above, the aqueous Ni concentration is substantially reduced from 2.0 to below 0.1 mg L −1 within 60 min. We then propose an alternative reaction pathway in which Ni II rather than EDTA is attacked by PMS, leading to the production of high-valent Ni species (in the form of EDTA-Ni IV =O). This is a key and highly oxidative species being further self-decomplexed to Ni III hydroxides. Our findings suggest that the involvement of Ni IV species might be a viable redox pathway that plays an important role in promoting decomplexation.
研究领域:
环境科学
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化学
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DOI
高影响因子
ENVIRONMENTAL TECHNOLOGY
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2024
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IF 2.2
Hao Zhang,Jiahong Wang,Peiling Han,Zhi Hu
Industrial wastewater often contains potentially toxic metals and it’s chelates, posing serious threats to human health and aquatic ecosystems, and adsorption is frequently used for the minimization of potentially toxic metals from water. In this study, citric acid modified MOF-808 (MOF-808-CA) was prepared by using citric acid to modify MOF-808 for the removal of Cr(III) and Cr(III)-EDTA from wastewater. MOF-808-CA with the BET surface area of 653.59 m2 g−1 and the pore volumes of 0.467 cm3 g−1 was successfully synthesized. The adsorption of Cr(III) and Cr(III)-EDTA by MOF-808-CA was 40.46 and 17.03 mg g−1 at pH 4.0 and 25°C, respectively. The adsorption isotherms and adsorption kinetics of Cr(III) and Cr(III)-EDTA were summarized using Langmuir-Freundlich isothermal adsorption model and the pseudo-second-order model. Even in high salinity wastewater (35,000 mg L−1), MOF-808-CA displayed a strong affinity for Cr(III) and Cr(III)-EDTA. The site energy (E*) values reduced with the increasing of adsorption capacities, and Cr(III) and Cr(III)-EDTA firstly dominated the high-energy adsorption sites before low-energy adsorption sites. The average site energies for the adsorption of Cr(III) and Cr(III)-EDTA by MOF-808-CA were 26.7 and 24 kJ mol−1, respectively, and the differences in the average site energies further illustrated the essential differences in their adsorption mechanisms. The adsorption by electrostatic adsorption and surface complexation were the main adsorption mechanisms for Cr(III) on MOF-808-CA, whereas hydrogen bonding and complexation were the main adsorption mechanisms for Cr(III)-EDTA on MOF-808-CA. The results showed that the MOF-808-CA adsorbent has a great potential for the removal of both Cr(III) and Cr(III)-EDTA from aqueous solutions.
研究领域:
环境科学
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材料科学
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产品关联
DOI
PubMed
高影响因子